‘Graphs’ are a method of organizing information using connections between different pieces of information, which are used in several different technical fields A graph is a collection of objects (for example, Facebook users), and a set of connections between them (e.g., whether the users have ‘friended’ each other). In the field's jargon, the objects in a graph are called “nodes” (that can be drawn as dots or labels), and a connection between two nodes is referred to as an “edge”.
Drawing graphs is often a difficult task, and a large amount of past and current research is devoted to devising visually informative graph layouts. One layout algorithm is the ‘force-directed layout’, where a physics-based simulation is used to draw the graph. Force-directed layouts have the advantage that they are very easy to set up, and can be generated automatically. However, these layouts (and many other automated layout methods) are often unintuitive, messy, and hard to understand.